[PATCH v2 3/6] lib: sbi: Add sbi_domain_check_addr_range() function

[Xiang W]

在 2022-11-23星期三的 16:27 +0530，Anup Patel写道：
> We add sbi_domain_check_addr_range() helper function to check
> whether a given address range is accessible under a particular
> domain.
> 
> Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> ---
>  include/sbi/sbi_domain.h | 15 +++++++++++++
>  lib/sbi/sbi_domain.c     | 47 ++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 62 insertions(+)
> 
> diff --git a/include/sbi/sbi_domain.h b/include/sbi/sbi_domain.h
> index 5553d21..4afcc37 100644
> --- a/include/sbi/sbi_domain.h
> +++ b/include/sbi/sbi_domain.h
> @@ -154,6 +154,21 @@ bool sbi_domain_check_addr(const struct sbi_domain *dom,
>                            unsigned long addr, unsigned long mode,
>                            unsigned long access_flags);
>  
> +/**
> + * Check whether we can access specified address range for given mode and
> + * memory region flags under a domain
> + * @param dom pointer to domain
> + * @param addr the start of the address range to be checked
> + * @param size the size of the address range to be checked
> + * @param mode the privilege mode of access
> + * @param access_flags bitmask of domain access types (enum sbi_domain_access)
> + * @return TRUE if access allowed otherwise FALSE
> + */
> +bool sbi_domain_check_addr_range(const struct sbi_domain *dom,
> +                                unsigned long addr, unsigned long size,
> +                                unsigned long mode,
> +                                unsigned long access_flags);
> +
>  /** Dump domain details on the console */
>  void sbi_domain_dump(const struct sbi_domain *dom, const char *suffix);
>  
> diff --git a/lib/sbi/sbi_domain.c b/lib/sbi/sbi_domain.c
> index f24a8e5..6d19d2c 100644
> --- a/lib/sbi/sbi_domain.c
> +++ b/lib/sbi/sbi_domain.c
> @@ -195,6 +195,24 @@ static bool is_region_before(const struct sbi_domain_memregion *regA,
>         return FALSE;
>  }
>  
> +static const struct sbi_domain_memregion *find_region(
> +                                               const struct sbi_domain *dom,
> +                                               unsigned long addr)
> +{
> +       unsigned long rstart, rend;
> +       struct sbi_domain_memregion *reg;
> +
> +       sbi_domain_for_each_memregion(dom, reg) {
> +               rstart = reg->base;
> +               rend = (reg->order < __riscv_xlen) ?
> +                       rstart + ((1UL << reg->order) - 1) : -1UL;
> +               if (rstart <= addr && addr <= rend)
> +                       return reg;
> +       }
> +
> +       return NULL;
> +}
> +
>  static int sanitize_domain(const struct sbi_platform *plat,
>                            struct sbi_domain *dom)
>  {
> @@ -303,6 +321,35 @@ static int sanitize_domain(const struct sbi_platform *plat,
>         return 0;
>  }
>  
> +bool sbi_domain_check_addr_range(const struct sbi_domain *dom,
> +                                unsigned long addr, unsigned long size,
> +                                unsigned long mode,
> +                                unsigned long access_flags)
> +{
> +       unsigned long pos = 0;
> +       const struct sbi_domain_memregion *reg;
> +
> +       if (!dom)
> +               return FALSE;
> +
> +       while (pos < size) {
> +               reg = find_region(dom, addr + pos);
> +               if (!reg)
> +                       return FALSE;
> +
> +               if (!sbi_domain_check_addr(dom, addr + pos,
> +                                          mode, access_flags))
> +                       return FALSE;
> +
> +               if (reg->order < __riscv_xlen)
> +                       pos += 1UL << reg->order;
addr+pos not always point to the beginning of the region, so the size of the
region cannot be added directly.

suggestion:
	pos = reg->base + (1 << reg->order) - addr

Regards,
Xiang W
> +               else
> +                       break;
> +       }
> +
> +       return TRUE;
> +}
> +
>  void sbi_domain_dump(const struct sbi_domain *dom, const char *suffix)
>  {
>         u32 i, k;
> -- 
> 2.34.1
> 
>